nixie clock

Here’s an offer from Intel and the guy behind all of reality TV [Mark Burnett]: win a million dollars for making something. Pitch an idea for wearable electronics to the producers by October 2, and you might be on a reality TV show about building electronics which they’re calling America’s Greatest Makers. With this, Intel is promoting the Curie module a tiny, tiny SoC with Bluetooth, IMU, and DSP functions. We’re of the opinion that a Hackaday reader should win this contest, or at the very least be featured prominently in the show. No, it’s not Junkyard Wars, but it’s still a million dollar prize.

The Luka EV is a semifinalist for the Hackaday Prize, and a completely open, road legal electric vehicle powered by hub motors. It also looks really, really cool. Now, they’re selling them. It’s €20,000 for a complete car. Did I mention how cool it looks?

Boca Bearings is having a ‘Show Us Your Workshop’ contest, with the best (or should it be worst?) workshop winning tool cabinets, tool kits, a work mat, and calipers.

The EMU Drumulator is a classic drum machine that featured dirty 12-bit drum sounds in ROM. Now, it’s a single chip thanks to [Jan]. He’s done a lot of great work putting synths in single chips, and it’s great to see him move on to classic drum machines.

There’s no doubting the appeal of Nixie tubes. The play of the orange plasma around the cathodes through the mesh anode and onto the glass envelope can be enchanting, and the stacking of the symbols in the tube gives a depth to the display that is unlike any other technology. So when [Ian] found a set of six tubes on eBay at a fire sale price, he couldn’t resist picking them up and incorporating them into a unique but difficult to read Nixie clock.

It turns out the set of tubes [Ian] ordered were more likely destined for a test instrument than a clock, displaying symbols such a “Hz”, “V” and “Ω”. Initially disappointed with his seemingly useless purchase, [Ian] put his buyer’s remorse aside and built his clock anyway. Laser-cut acrylic, blue LEDs under the tube for a glow effect, a battery-backed RTC talking to an ATmega328, and the appropriate high-voltage section lead to a good-looking and functional clock, even if [Ian] himself needs a cross-reference chart to read the time. You’ll be able to figure out at the whole character set after watching the video after the break; spoiler alert: sensibly enough, Ω maps to 0.

Nothing quite beats the warm glow of a tube. What better way to enjoy that glow than to use it to read numbers? Nixie tubes were created by Haydu Brothers Laboratories, and popularized by Burroughs Corp in 1955. The name comes from NIX I – or “Numeric Indicator eXperimental No. 1”. By the mid 1970’s, seven segment LED’s were becoming popular and low-cost alternatives to Nixies, but they didn’t have the same appeal. Nixie tubes were manufactured all the way into the 1990’s. There’s just something about that tube glow that hackers, makers, and humans in general love. This week’s Hacklet highlights the best Nixie (and Nixie inspired) projects on Hackaday.io!

We start with [Sascha Grant] and Nixie Temperature Display. [Sascha] mixed an Arduino, a Dallas DS18B20 Temperature sensor, and three IN-12A Nixie tubes to create a simple three digit temperature display. We really love the understated laser-cut black acrylic case. An Arduino Pro Micro reads the Dallas 1-wire sensor and converts the temperature to BCD. High voltage duties are handled by a modular HV power supply which bumps 9V up to the required 170V. Controlling the Nixie tubes themselves are the classic K155ID1 BCD to decimal converter chips – a favorite for clock builders.

Next up is [Christoph] with Reading Datasheets and Driving Nixie Tubes. Chips like the K155ID1, and the 74141 make driving Nixie tubes easy. They convert Binary Coded Decimal (BCD) to discrete outputs to drive the cathodes of the Nixie. More importantly, the output drivers of this chip are designed to handle the high voltages involved in driving Nixie tubes. These chips aren’t manufactured anymore though, and are becoming rare. [Christoph] used more common parts. His final drive transistor is a MPSA42 high voltage NPN unit. Driving the MPSA42’s is a 74HC595 style shift register. [Christoph] used a somewhat exotic Texas Instruments TPIC6B595 with FET outputs, but any shift register should work here. The project runs on a Stellaris Launchpad, so it should be Arduino compatible code.

[Davedarko] has the fixietube clock. Fixietube isn’t exactly a Nixie. It’s an LED based display inspired by Nixie tubes. Modern amber LEDs aren’t quite the same as classic Nixies, but they get pretty darn close. [Dave] designed a PCB with a 3×5 matrix of LEDs to display digits. A few blue LEDs add a bit of ambient light. The LEDs are driven with a 74HC595 shift register. The entire assembly mounts inside a tiny glass jam jar, giving it the effect of being a vacuum tube. The results speak for themselves – fixietubes certainly aren’t Nixies, but they look pretty darn good. Add a nice 3D printed case, and you’ve got a great project which is safe for anyone to build.

Finally, we have [Johnny.drazzi] with his Open Nixie Clock Display. [Johnny] has been working on Open Nixie for a few years. The goal is to create a Nixie based clock display which can be driven over the SPI bus. So far, [Johnny] has 6 Russian IN-12 tubes glowing with the help of the ubiquitous K155ID1 BCD to decimal converter. The colons of the clock are created with two INS-1 neon indicators. [Johnny] spends a lot of time analyzing the characteristics of a Nixie tube – including the strike voltage, and steady state current. If you’re interested in building a Nixie circuit yourself, his research is well worth a read!

Nixie tubes, while built during the vacuum tube era of the mid-20th century, still exist in a niche among hackers. It’s quite the task to get them up and running due to a number of quirks, so getting an entire clock to work with Nixie tubes is a badge of honor for those who attempt the project. For anyone thinking about trying, [Tomasz] has written an extremely detailed write-up of his Nixie clock which should be able to help.

There is a lot of in-depth theory behind Nixie tubes on [Tomasz]’s page that he covers in the course of describing his clock. As far as the actual project is concerned, this is a simplified design which uses one board for the entire clock, including circuits for the lamps, drivers, microcontroller, power supply, and DC/DC conversion. This accomplishes his goal of making this project as small as possible. The Nixies he chose were IN-12 which are popular in his Eastern European home, but could be sourced from eBay and shipped anywhere in the world.

There is a lot of documentation on the project site, including schematics, microcontroller code, PCB design, and even screenshots of the oscilloscope for various points in the circuit. While this might not be the simplest Nixie clock ever, it is certainly close, more easily readable, and the most detailed build we’ve seen in a while!

There’s no shortage of Nixie-related projects online, but this vertical wall clock is a solid build and looks pretty sleek. [andreas] actually sourced the wood from an old handrail, into which he drilled six holes for the tubes with 30mm bits, then treated it with some woodworm poison after noticing holes his drill wasn’t responsible for.

The schematic is what you’d expect for a Nixie clock, designed with 123D circuits. [andreas] provides both top and bottom layers in a high-res PDF if you’d prefer to etch your own boards at home rather than order a PCB from the man. He took the finished board and soldered all the components in place, using tape to prevent some short circuit possibilities and mounting the result onto a pair of black plastic rails. The entire assembly mounts to the wooden case and is rounded off with glued-on end caps and a back cover. As always, be aware of the danger presented by the high voltage requirements of Nixie Tubes, and don’t go licking the components.

He was first exposed to nixie tube clocks a few years ago when his brother gave him a DIY nixie clock kit from [Peter Jensen’s] website TubeClock.com — it was an easy build, and worked very well. It also introduced him to a unique driver for nixie tubes, an HV5622 high-voltage shift register made by Supertex inc. Compared to the traditional (and rare) 74141 nixie driver chips or discrete transistor drivers, the HV5622 is much smaller, requires less microcontroller I/O’s, and is not as picky when it comes to powering it.

The nixie tubes he chose for the project came from a lot sale on eBay, Russian surplus IN-12 tubes. He even managed to find an english datasheet for them!

[Localroger] says the board dates to about 1975. It’s all TTL, no microprocessor anywhere. He was headed to the Dumpster with it in the mid-1980s, but realized that he could hack it into something useful. Since the display wasn’t multiplexed, it would be fairly easy. He used it as a BCD tester for about 10 years until the method fell out of fashion.

After a decade on the shelf, [Localroger] started off for the Dumpster once more with the board. The nixie tube display cried out for another chance to glow, so he decided to repurpose it into a remote-controlled bedside clock with an alarm. He installed a Parallax Propeller Protoboard with headers for easy removal and subsequent servicing of the 5775 board. He added a few things to the protoboard: a piezo element for the alarm, a SparkFun RTC module, an IR receiver, and vertically-oriented header so the PropPlug can be plugged in from the top. But that’s not all. [Localroger] designed a custom melamine-finished MDF enclosure and laser cut it, giving the edges a nice contrast. It’s so tough, he can put his ceramic lamp on top of it to save space on the nightstand.

Nixie tubes are becoming more scarce all the time. If you can’t find any, we humbly suggest rolling your own.